Wrought-metal pole-arm.



No. 857,938. PATENTED JUNE 25, 1907.

' M. E. HARRISON.

WEOUGET METAL POLE AEM.

APPLIOATION FILED JAN. 11, 1906'.

2 SHEETS-SHEET 1.

No. 857,938. PATENTED JUNE 25, 190'7. M. E. HARRISON. WROUGHT METAL POLE ARM.

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'To a/ZZ whom it may concern:

lll/L/-XRIIN EMMITT HARRISON, OF PARNASSUS, PENNSYLVANIA.

wRouGHT-METAL POLE-ARM.

Speccatipn of Letters Patent.

Patented Jime 25, 1907.

Application filed January 11, 1906. Serial No. 295,552.

Be it known that I, MARTIN EMMITT HAR- nrsoN, a citizen ofthe United States, residing at Parnassus, in the county of Westmoreland and State of Pennsylvania, have invented certain new Iand useful Improvements in Wrought-Metal Pole-Arms; and I do declare the 'following to be a full, clear, and exact description ofthe invention,` such as will enable others skilled in the art to which it appertains to make and 'use the same, reference being had to the accom anying drawings, and to the letters and gures of reference marked thereon, which form apart of this specification.

This invention relates to a new article of manufacture, and it com rises the making from a sheet of metal o a telegraph pole cross-arm, which will be strong, durable and of simple construction, adapted to take the place of the wooden arms now in general use, together with means for supporting or attaching the insulator pins in position -thereon, a means for securing said arm to the pole, also the peculiar form of construction to give the arm the greatest direct and lateral strength, the bending and shaping of the top to form a water-shed for the preservation of the arm, together with other of certain details of construction, as will be fully described hereinafter. f

In the accompanying drawings z-Figure 1 is a side elevation of myimproved cross-arm for telegraph' oles, a part ofvwhich is shown in section an -one of the ends broken away. Fig. 2 isa plan view of the same, also havin a part in section. Fig. 3 is a sectional en elevation taken on the-line y y ofvFig. 2. Fig. iis ,a side elevation of a-modifled form of the cross-arm, showing the construction used in connectionwith Wooden insulator ins such as are now in common use-.ff Fig. 5 1s an inverted plan view ofthe same'. Fig. 6 is a plan View of a small portion of the arm, showing one of the flanged openin s for the reception of the shank of thefinsu ator pin.

Fig. 'Z is an end elevation of the cross-arm,- showlng an insulator pin 1n positlon.

To construct a telegraph pole cross-arm iny accordance with my invention, I provide a piece of sheet metal, such as steel, of the Iproper width and length, and by means of suitable diesand press, bend the said sheet to a form substantially U shaped in cross section, (see Figs. 1 2 and 3,) leaving an open bottom, the sides 1` being parallel with each other, and the top higher along itsV central longitudinal line than at either side, to form awlater-shed 2. This water-shed 2 may be in the angular form shown at Fig. 3, 'or simply curved or bowed in such manner as to precipitate the water during rain storms.

ormed through the top ofthe cross-arm and at regular intervals, are openings 6 for the reception of the shanks of insulator pins 5, which are now manufactured for the purpose of sustaining wires, in two forms, the one of metal and the other of wood, both of which are shown in the drawings. These metal pins 5 are formed with a flanged threaded shank, and are attached to and made rigid with the cross-arm by means of a nut, Knotl shown) while the wooden ins 5 are simplyA placed in sockets, as will e vdescribed hereinafter. Surrounding theopenings 6 for these pins is a slightly elevated boss 4,

lpressed outward from the metal'to form a Vflat surface at right-angles to the plane of the sides 1 of the arm, and serving as a bearing for the ange of the insulator 1n.

The 4sides 1 of the arm are ormed with inwardly pressed ribs 3, and extend from the ends of said arm to points a short distance at either side` of the longitudinal center of the same the object bein to stiffen the sides (by thus bendin the meta )against lateral strain.

.To attach t e cross-arm to the telegraph or other pole, bolt openings are formed through the sides 1, at the middleor center' of its length, the one opening indirect horizontal line with the other, and through which a bolt 7- is passed, the said bolt being .fitted with a separating piece 9 and projected through said pole and secured b awasher and nut, in a marmer common in t e art. This parting piece-9 I prefer to form from sheet metal, the contour of which is the same as the inside lines of cross-section, and is adapted to fit snu ly within said arm and held in pf sition byt e bolt 7 passing throughV a slotted portion A10, bent outwardly from either side of the plate. f This parting plate 9 will hold the lsides in line agtinst the strain caused by the tightening of t e bolt 7. To further support the cross-arm. in position onthe pole 8, diagonally-arranged braces 1 1 are attached to one of the sides 1 of the arm by rivets 12 and the free ends attached to the pole 'some distance below the level of the said arm. L.

The above description relates exclusively IOO rio

to that form of a cross-arm wherein metal insulator pins 5 are used, and in order that woodenpins 5 may be attached and vused with this class of cross-arm, it is necessary to I the cross-arm is formed from a plate or sheet of metal bent substantially the same as that .previously described, and having the side walls 1 at a portion of the middle substantially U shaped in cross-section, and a portion-of each lower half of said sides bent inwardly, leaving a narrow s ace 14, which construction serves the dou le purpose of strengthening the arm against direct and lateral strains, and affords a means for supporting'the lower end or shank of the wooden pins; 5', the metal at which points being eX- pandedl to :lit neatly about opposite sides of said pins, as will be best seen by reference to Figs. 5 and 7, of the drawings. The watershed 2 and bosses 4 are the same as before described, and if it is desired, the metalY about the perimeter of the openings 6 for the insulator pins may be flanged downward, (see Figs. 6 and 7) and made to present a broad surface for the support of the upper part of the shank of said pin. The braces 1 l may be attached to one of the side walls by rivets 12, or said rivets passed through both walls, as shown at Figs. 4 and 5 of the drawings. The means employed for attaching this form of cross-arm tothe pole 8, is identical with that of the other. form shown andv described.

These arms arel made in various lengths and strenfgth of material, and are painted, galvanize or otherwise coatedfor protection against the weather, and have many advantages over the ordinary wooden crossarm now in general use, the'metal arm being lighter and of eater strength and can be produced at a out or somewhat less cost than said wooden arm, .which latter is of carefully selected wood, free from knots and flaws, as of necessity they must not only support the wei ht of the wires, but `at times, one or more linemen, whose life, probably,.-

- depends upon the strength of said arm. Anlother and important advantagevin this wrought metal arm covered with a weatherproof material, is, that 'it is practicably indestructible, and has several times the life of the wooden arm.

It is obvious, that this sheet metal cross' arm may be formed in a variety of different shapes best suited to the circumstances under which it is used. Therefore I do not wish to conine myself to the exact details of construction, but wish to claim all such modified forms as would come properly wi thin the general scope of the invention,

clined to vprovide a water shed. 2. As a new article, a pole arm constructed from a single sheet of metal folded longitudinally toforni spaced sides and a connecting web with s aidweb reversely inclined to,prol vide .a water shed, a stay member transversely disposed between said sides.

3. As a new article, a pole arm constructed i from a'single sheet of metal folded longitudinally to form spaced sides and a connecting web with said web portion reversely inclined to form a water shed and with said sides corrugated longitudinally between the central` portion and the ends of the same.

. '4. Asa new article, a pole arm constructed from a single sheet of ymetal folded longitudinally tovform spaced sides and a connecting web with said webl reversely inclined to provide a water shed, a stay member .disposed transversely between said sides centrally of the arm, and said sidescorrugated longitudinally between said stay and the ends of the arm.

5. As a new article, a pole larm constructed from a single sheet of metal folded longitudinally to form spaced sides and aconnecting web and with spaced insulator pin receiving apertures in said web portion,and withsaid spaced sides compressed and with recesses corresponding to and in alinement with said insulator pin apertures and adapted to embrace said pins from opposite sides.

6:' As anew article, a pole arm constructed from a single sheet of metal folded longitudi- -nally to form spaced sides and a connecting web with said web portion reversely inclined to provide a water shed, a stay member extending between said sides centrall of the arm and provided with transverse soc ets and a securing bolt extending through said sides IOO IIO

and the sockets in said plate toprovide means for fastening the arms to the pole.

7. Asa new article, a pole arm constructed from a single sheet of metal folded-longitudinally to form'spaced sides .and a connecting lweb and with spaced apertures in said web' and with said sides compressed and providedl with recesses corresponding to'andin aline-- y ment with said apertures and adapted to' partly embrace the insulator pins, a stay mem er extending between said `sides centrally of the arm and provided with transverse sockets, and a securing bolt extending through said sides and said sockets and providing means for fastening the arm to the po e. v

8. A new article of manufacture, comprising a pole-arm `formed from Wrought sheet metal bent in theform of the letter U, in

cross-section, said arm being provided on its top with an inclined surface to forni a watershed, means for attaching theinsulator pins thereto and a means for attaching the arm to a pole.

9. A new article of manufacture, coi'nprising a pole arm formed'from wrought sheet metal and substantially U shaped in crosssection, said arm being provided on the top with inclined surfaces to form a water-shed and with openings for the reception and support of insulator'pins and a means for attach ing said arm to a pole.

10. A new article of manufacture, comprising a pole-arm formed from wrought sheet met-al, said arm being formed on its top with a water-shed and having a portion of its sides bent inwardly in parallel lines and a part of the center substantially U Ishaped in .means for attaching said arm to a pole.

12. A new article of manufacture, compusing a pole-arm formed Jfrom wrought sheet metal and substantially U shaped in crosssection, in combination with a means comprising a bolt and parting piece for attaching said arm to a pole. y i In testimonyT whereof, I aHiX my signature in presence of two witnesses.

MARTIN EMMITT HARRISON. Witnesses:

D. L. PATTERSON, JOHN. C. THOMPSON. 

